Combined throttle and trip valve



Feb. 15 1927.

W. E. BUTLER COMBINED-THROTTLE AND TRIP VALVE Filed April 19, 1922 4Sheets-Sheet 1 Inventor. WM 8. 43M?! Feb. 15, 1927. 5

W. E. BUTLER COMBINED THROTTLE AND TRIP VALVE Filed April 19 1922 4Sheets-$heet 2 7 w\ \\\\\\\M m 1 ,1 n W f/lll /y WV /M \5 J w 1 9N 77/ Am w7 2 4 m z a /w v. N wflk m M 6 M V a 0 F b. 15 1927. e w. E. BUTLERCOMBINED THROTTLE AND TRIP VALVE 4 Sheets- Sheet 5 [12b tox 2M Feb. 15,1927. 1,617,895

w.;I-E. BUTLER COMBINED THfibTTLIJ AND TRIP VALVE Fil ed April 19, 19224 Sheets-Sheet 4 Patented Feb. 15, 1927;

- UNITED STATES PATENT OFFICE.

, WILLIAM 'nnnswonrnnu'rnnn, or nnwnunvron'r, 'MAssAcHUsETTs.

COMBINED THROTTLE AND TRIP VALVE.

Application filed April 19, 1922. Serial No. 555,562.

as for example, when the speed of the engine or turbine becomesabnormally high.

It is the chief object of the present invention to devise a valve ofthis character which will be very reliable in operation, can bemanufactured economically, shall be suited to installation under agreatvariety of conditions, and which. generally will satisfy thepractical requirements of an apparatus of this character. The inventionalso aims to devise a valve mechanism which can be used satisfactorilyfor starting and stop ping the engine under normal conditions, as wellas under emergency conditions.

.The nature of the invention will be readily understood from thefollowing description when read in connection with the accompanyingdrawings, and the novel features will. be particularly pointed out inthe appended claims.

in the drawings, I 1 Figure 1 is a View, partly in side elevation andpartly in cross section, of a valve COIlSlZTftlCtGd in accordance withthe present invention;

Fig. 2 is a cross sectional view of a portion of the operating mechanismfor the valve shown in Fig. 1;

Fig. 31s a view, partly in slde elevation and partly in cross section,of the control-.

ling mechanism for the valve; and

Fig. 41 is a side elevation of a part of the controlling mechanism shownin Fig. 3.

Referring first to Fig. 1, 2 designates a portion of the steam chest ofa steam engine, turbine or the like, 3 a valve casing bolted to thesteam chest 2, and dthe end of a steam line which conducts steam to thevalve. \Vithin the casing 3 is a valve 5 having a valve stem 6 connectedthereto in the usual manner so that the valve can have a limitedmovement relatively to the stem but is compelled to move therewih towardand from a valve seat 7. These parts constitute a typical throttle valvearrangement for a steam engine.

The valve stem 6 projects through the wall of the casing 3 into anothercasing or housing 8, Figs. it and 2, which is bolted to the casing 3,and; the stem is held against rotation by means of a key 9 seatedtherein and projecting into a groove formed in a bushing 10 which issecured in the adjoining walls of the two casings 3 and 8. A threadedsleeve 12 is secured on the end portion of the stem 6 by means of a nut13 which forces the sleeve against a shoulder on the stem so that thissleeve forms, in effect, a continuation of the stem. threads of the part12 engage with themternal threads of a nut l'having a shank 15 which isgrooved to receive two keys or splines 16 16. These keys are seated "ina shaft 17 which is coaxial. with thepartsfi, 12 and 1.4, and projectsthrough the end of the casing 8. The shaft 17' carries a collar 18 whichcooperates with a bracket 19 secured to the casing 8 to hold the shaftagainst axial movement but permits it to be rotated. A stuffing box 20encircles the shaft 17 where it emerges from the bracket 19, and ahand-wheel 21 is secured to the end thereof and provides a convenientmeans for rotating the shaft.

The nut 14 has a peripheral groove 24 formed therein to receive pinsorrolls 25 which are carried by a forked or bifurcated arm 26 thatstraddles the nut and is secured fast on a rock shaft 27 located abovethe valve stem and extending transversely thereto. Another arm 28 issecured fastto this rock shaft outside the casing 8, and with the arm 26forms, in effect, a bell crank lever. -A weight 29 connected to the arm28 by a linlc 30 tends, through its connections with the valve, to holdthe valve in its closed position as will be obvious from an inspectionof Fig. 1. Normally this movement of the valve is restrained. by a latch32 which is pivoted on the upper end of a standard 33 and has a-hook toengage a pin 34 projecting laterally from the arm 28. A leaf spring 35acts on the latch 32 to hold it in its'latching position. For thepurpose of releasing the latch 32 a weighted lever 36 is fulcrumed onthe top of the casing 8 at'37 and carries a lug 38 which is adapted tostrike the upper curved face of the latch 32 and swing it on its pivotina direction to release the pin 34. Normally the lever 36 is held in itsuppermost. position by ament is then stoppedby the engagement of I TheEU in}; tor\\ "ard as a unit.

stem.

nut 14, as shown in Fig. 2, and the instant that the latch 32releases'the pin S t-"the weight 29 operates through its connectionswith the nut 14 to slide the valve toward its seat 7,'allthe parts 5, 6,12 and l t slidv i 'lhe flow of steam through the valve tends to slamthis valve againstits mean .1 in order to reduce the rate of the valveclosing movement a dz 11 pet mechanism is'connected with the valve vThis mechanism comprises an arm elfltast on the shatt 27 and connectedbyt linkffl8 with a. rod 44 which is guided for vertical movement. Apiston 45 is secm-"ed to the lower end of this rod and works w inacylinder or dash pot 46 containing oil or other suitable fluid. Whenthe latch 32 isles-aged and the valve 5 starts to close, F the piston'45is forceddownwardly, and the liciiiid below the piston flows through twobypasses QT-and ds'into the upper part of' The rate of the cylinderabove the piston. fitiw the liquid through the by-passfiS is controlledby adjusting" a valve 4:9 which 'is included in this hy-pass. W'ith thisar- 30 rangem'ent, therefore, the rate of the closing .nioveiri ent oithe valve can he controlledas desired. During the latter part or" thismovement theoil escapes through theby- .pass 48 only, so that byadjusting the valve LQ'it-he valve 5 may be caused to seat very gently.Upon theupward movement of the jpist'on 45, which occurs during theresetting of theappiiratus, the oil flows through holes formed in thepiston 45, these holes being "closed during the reverse movement by avalve 50wh1'ch normally isheld in its closed position by a light spring5.

Immediately "atter the valve 5 has been closed, the valve stem, and theparts immediair-51 connected therewitlnore in the posi- 50 14bacliwardly,' the part 12 remaining sta 't'ionary. Thismovement"automatically results in retu'r1nnc'the lovers 28*and 42 to"their nntlalj positions, as shown in F l,

and re eugafl'es the'pin 34;with the latch' i 'jl' ed theparts are 111the-position shown WVhen this movement has been come in Figil. fBv/thenreversing the movement "the"lia-nd wheel"21 the threaded member 12- willdrawn backwardly within the nut husopening the valve 5 and admitting 1nto'ft he engine. lVhen theflange on fth 'p a irt" IZlstri'kes the end ofthe nut '14: the

'1g' mov fiint'ot the valve is stopped,1

tl stime ing in the running oft emtive position ivhe-re my will remainuntil the'la'tcli 32 is nipped again, or the valve is closed byoperating the hand-wheel 21.

The "control-ling apparatus for" the mecha nism above described is bestillustrated in 'Figs. 3 and t, and comprises a governor mechanismmounted in any convenient locationand pretera'bly driven through a beltconnection with the main shaft of the engine. 'This governormechanismcomprises a bracket fiTsu'pportinga' shatt 58 having a pulley 13E)thereon to receive the bolt 57 This shattalso carries a hevel'g car 159di'iv- 'ing anotherhevel gear GO having ahracket (31 secured theretoanddnounted to rotate about a vertical axis. This bracket-has two setsof'leat springs"63 63 sectired thereto, the masten'leaf of each set'supporting at its'upper endfa governor'ball 62. These bulls areconnected by links to a sleeve 64 which is mounted in the hra'ckettlandencircles a rod 65 that projects tln'ouigh the entire length of thesleeve and'is nrovidedat its upper end with a 'head' overlying" the endof the sleeve. Vi hen" tl1e"hal'ls 62 62 are thrown outwardlvbvcentrifugal inerti a upon an increase in their speed of rotation.theywill lift the sleeve Stand with it 'the rod 65. This l'ittinmovement is yielding'lv opposed by a spring"68, Fi 4, bearing againstahlock 69 that pressesagrainst. an arm 70 securedtast'in arockshatt 71.The ro clr 'shatt has anotherarni 72 secured thereto which is pivoted toa collar 73 secure'd fast on the rod. The spring 68 is backed up by anadjusting screw 74 provided with a h and wheel 75"afnd a check nut76holds' the screw 111 its adii ted posi ion. hen the collar 73 risestar enough, 'i.t strilies the inner end of one arm T7 of a hell cranklever pivoted at 78 and having; anotherarniTQ which no!- nially'overlies the end oian arm 80, Figs.

3 and t. A light spring 81 tends to hold the levcrTS) in the positionshown in Fig. -i-. The arm projects "tln'oug'lr an opehingi be tween thenifeinhers ot'a :torlred bracket 8:. and is "tulcruined nt '83. Formedon this arm a l'ioolstll which normally"engages a link 85011 'theend'o't a cord, chain, or the like," 86, which is "guided over"suitablepidlcys and runs to the tree end of the wciehtcddever 2%, Fig.l. v

This niechanisnn there tor. normativ-holds thelever tlti in its elevatel'p'osition. iVl-ien. 3 however, the speed of rotation of the main shaft"56 increases above a predetc lined point; the rod 65 will he lifted .Q,i the action of the governor ha ls. as above described. thus causing thec'ollariil to swinL the hell crank. lever "77 791 11 a "count-enclockwise directiom Fig. 4, far enough to re leaselt-he' end of the. arm80, whereupon this arm will swing upwardlyirel asing thelini: Strandthereby-allowing the 'xveighted lever 36 to drop. This willitrip'th'elatclri32 'and allow the valve to close in the manner previouslydescribed.

When it is desired to reset the mechanism, the arm is swung back intoits horizontal position, as shown in Fig. 3, the link first beingengaged with the hook 84. The arm will be held in this position by thelatch or lever 7 9 until tripped again by hand or by an abnormal speedcondition. In'order to facil" itate the engagement of the link 85 withthe hook 84C, in case the connections run overhead, a handle 88 isconnected'to the cord 86, as shown in Fig. 3.

In many installations it is desirable to provide an additional controlthrough which the valve can be tripped manually from a distant point.This condition is provided for conveniently in the arrangement shown bysecuring an arm 90 to the rock shaft 71 of the governor mechanism,connecting this arm through a link 91, bell crank lever 92, link 98,lever 94, link 95, and lever 96 to a rod 97 having a handle 98. Bypulling the handle 98 the rock shaft 71 will be moved in a direction tocause the collar 73 to trip the latch or lever 79, thus releasing thearm 80 and causing the valve to close in the manner above described.

It will now be appreciated that this invention provides a simple form ofmechanism which will operate automatically to close the valve and shutdown the engine or turbine controlled thereby under abnormal speedconditions. The parts of the mechanism are rugged and substantial and itis, therefore, not liable to get out of order. A particular advantage ofcombining this mechanism with the throttle valve of an engine is thatthe apparatus must be operated at least twice a day under normalconditions so that it does not have an opportunity to get out of orderwithout that fact being known a once. It therefore avoids the seriousobjection tomost safety mechanisms, that they are not subjected tofrequent usage or inspection, and when an emergency happens the safetyaliiparatusfails to function because it has in the )meantime becomedeffective in some manner without such defect being known. A further alvantage of this mechanism is that it does not require the breaking ofthe steam line to install, the installation being made directly at thethrottle valve. The valve cannot be opened without setting the safetyapparatus, so that it is impossible to start up the engine wihout havingthe safety mechanism in condition to operate,

\Vhile I have herein shown and described the best embodiment of niyiinvention of which I am at present aware, it will readily be appreciatedthat this embodiment may be modified in many particulars withoutdeparting from the spirit or scope of this hand-wheel connected withsaid nut to rotate the nut, a weighted lever connected with said nut tocontrol the longitudinal movement of the nut, and a latch for holdingsaid lever in a given position.

2. An apparatus of the character described comprising, in combination, avalve, a casing therefor, a screw threaded stem for said valve heldagainst rotation, a nut engaging the threaded portion of said stem, ahand-wheel connected with said nut to rotate the nut, a latch,connections between said latch and nut for holding the valve normally inits open position, means for releasing said latch, a dash pot having apiston therein, and connections between said valve stem and said dashpot enabling said dash pot to reduce the rate of the closing movement ofsaid valve.

3. An apparatus of the character described comprising, in combination, avalve, a casing therefor, a screw threaded stem for said valve heldagainst rotation, a nut engaging the threaded portion of said stem, ashaft having a splined connection with said nut, a hand-wheel on saidshaft, means for holding said shaft against axial movement, said nuthaving a groove in its peripheral surface, a bell crank lever havingparts to engage said groove tocontrol the longitudinal position of thenut, a weight connected with said lever and tending to move the lever toclose the valve, and a latch for restraining said movement of the lever.

at. An apparatus of the character described comprising, in combination,a valve, a casing therefor, a slidable stem connected with said valvefor operating it, an externally threaded sleeve secured on said stem, aninternally threaded nut engaging the threads of said sleeve, a shafthaving a splined connection with said nut, a hand wheel on said shaft,means for holding said shaft against axial movement, and a latchmechanism connected with said nut for holding the valve normally in itsopen position.

WILLIAM ELLSVVORTH BUTLER.

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